Make AXPlatformNodeDelegate::GetData() const

ui/views/accessibility/native_view_accessibility_base.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_ACCESSIBILITY_NATIVE_VIEW_ACCESSIBILITY_BASE_H_
 #define UI_VIEWS_ACCESSIBILITY_NATIVE_VIEW_ACCESSIBILITY_BASE_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 22 matching lines @@
   ~NativeViewAccessibilityBase() override;
 
   // NativeViewAccessibility:
   gfx::NativeViewAccessible GetNativeObject() override;
   void NotifyAccessibilityEvent(ui::AXEvent event_type) override;
 
   // Focuses or unfocuses a View.
   bool SetFocused(bool focused);
 
   // ui::AXPlatformNodeDelegate
-  const ui::AXNodeData& GetData() override;
+  const ui::AXNodeData& GetData() const override;
   int GetChildCount() override;
   gfx::NativeViewAccessible ChildAtIndex(int index) override;
   gfx::NativeWindow GetTopLevelWidget() override;
   gfx::NativeViewAccessible GetParent() override;
   gfx::Vector2d GetGlobalCoordinateOffset() override;
   gfx::NativeViewAccessible HitTestSync(int x, int y) override;
   gfx::NativeViewAccessible GetFocus() override;
   gfx::AcceleratedWidget GetTargetForNativeAccessibilityEvent() override;
   bool AccessibilityPerformAction(const ui::AXActionData& data) override;
   void DoDefaultAction() override;
@@ skipping 15 matching lines @@
   // tree.
   Widget* parent_widget_;
 
  private:
   void PopulateChildWidgetVector(std::vector<Widget*>* result_child_widgets);
 
   // We own this, but it is reference-counted on some platforms so we can't use
   // a scoped_ptr. It is dereferenced in the destructor.
   ui::AXPlatformNode* ax_node_;
 
-  ui::AXNodeData data_;
+  mutable ui::AXNodeData data_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeViewAccessibilityBase);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_ACCESSIBILITY_NATIVE_VIEW_ACCESSIBILITY_BASE_H_